Pulp-stone-dressing bur



C. B. AIKIN ET AL PULP STONE DRESSING BUR Filed June 24-.- 1922 Dec. 4, 1923. 1,476,571

Patented Dec. 4, 1923.

CECTL B. AIKEN AND FRANK W. AIKIN, OF WATERTOWN, NEW YORK.

PULP-STONE-DRESSING BUR.

Application filed June 24, 1922. Serial No 570,698.

To all whom, it may concern."

Be it known that we, CECIL B. AIKIN and FRANK \V. Ainiir, citizens of the United States, residing at lVatertown, in the county of Jefferson and State of New York, have invented certain new and useful Improvements in Pulp Stone -Dressing Burs; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

This invention relates to burs for dressing wood pulp grindstones and has for an object to provide a bur which will produce in the face or periphery of the grindstone the desired configuration and at the same ime will properly clear from the grooves or furrows cut in the stone without breaking out parts or corners of the stone operated upon.

It is well known that in the dressing of wood pulp grindstones a serration or reticulation of the surface is produced by holding against the rotating stone a bur having complementary contours and'that the action of the bur rotating in consonance with the stone dresses down the stone to the required or desired contour.

The contour of the stone usually employed is that produced by a plurality of grooves or furrows in the face of the stone which may be parallel with the axis of the stone or may run at an angle to the axis; that is to say, spirally upon or about the face of the stone. Such grooves are usually V-shaped. bur which produces these V-shaped grooves must be the complement; that is to say, it must be provided with ribs whose contour is the complement of the grooves in the stone and whose grooves are the complement of the ridges upon the stone.

In the operation of burs upon the surface of the stone, it has been found impractical to produce the desired contour because of the fact that the grooves in the burs are so shaped that in clearing from the stone, as the two rotate in engagement, the corners of the ribs of the stone are broken 01f in irregular and jagged shapes. The present invention provides a bur having ribsand.

It is obvious, of course, that theribs on its periphery which are relatively or comparatively thin and sharp, separated by grooves, the bottoms of which are substantially flat or correspond substantially to the circumference of the body of the bur with rounded corners intervening between the flat portions and the sides of the ribs.

With these and other objects in view the invention comprises certain novel features, elements, contours, configurations and functions, as disclosed in the drawings, together with equivalents thereof, as will be hereinafter more fully described and claimed.

' In the drawings:

Figure 1 is a view in section taken substantially perpendicular to the axis of rotation of the bur, showing a fragment of the bur greatly enlarged and showing in dotted lines a grindstone being dressed;

Figure 2 is a view, partly in side elevation and partly in longitudinal section of the type of bur wherein the ribs run substantially parallel to the axis;

Figure 3 is'a view, partly in side elevation and partly in section, of a bur of the type wherein the ribs are arranged spirally.

Like characters of reference indicate corresponding parts throughout the several views. Y

The bur which enters into the present application and is indicated as an entirety at 10 may be of hollow formation to fit upon a center or mandril, or may be solid With only a journal bearing through its axis, or may be mounted and j ournaled' in any other or any usual and approved way.

The physical construction of the body of the b-ur or its manner of mounting or journaling is wholly immaterial to the present invent-ion and is adapted to conform to the usual practice.

About the face or periphery of the bur, a plurality of ribs are formed having sides 11 acutely converging to a point or line 12. As explained in the objects. of invention, these ribs soi outlined may be disposed longitudirf Fries;

nally of the body or in parallelism with the ing sides 11 are spaced apart about the periphery of the, body 10 with sections 13 in: tel-lying the ribs which are suhsta'ntial-ly flat or may conform :to the curvature of the body of the bur. Interposed between these flat surfaces 13 and the side tape-rs 11 are conce ve or rounded corners 1-5 As will be noted from Figure .1, especially at the points 15 and 16 the rounding of these corners of the grooves interposed between the files is such that the ribs o'i' teeth themselves will exactly clear the rounded or conve-Xcorners of the di'es'sed portion of the stone, indicated as an entirety at 17. In the ordinary action of such burs upon at stone of the type, the i'esu'lt of drawing the teeth or rih over the corner of the dressed stone, corresponding to the points 15 or 16, is to bi'eakthe stoneinto irregiiler and jagged surfaces, which is undesirable in the production of uniform pulp. By providing the bun with the rounded corners in the bottoms of these grooves, this result isavoided and a, stone of uniform dressing is produced the use o1 the bur as distinguished from a rugged onhroken surface produced by a bur which is not; provided with such round-cornered grooves.

The operation of this bur when dressing 2: stone is exactly the same as the 'oiperwtion employed in the dressing of stones withthe bur which are commonly in use, so theta description of the operation would Add nothing to the understendability of the invention as slime described.

What we cle' to be new is:

A pulp stone di ssing but rovided with a plurality of spaced i'ibs'defin'ing inteiflying grooves, the bottoms of which aresubstantially flat, merging into the inclined sides of the ribs by concave sui'fztces extending from said flat bottoms to the inclined sides.

In testimony whereof we hereunto our signatures.

FRANK W. AIKIN. CECIL B. AIKIN. 

